{{/* Table of Contents */}}
{{/* TODO: toc bottom part should be able to hide */}}
{{- $toc := .Params.toc | default true -}}
{{- $onThisPage := (T "onThisPage") | default "On this page"}}
{{- $editThisPage := (T "editThisPage") | default "Edit this page"}}
{{- $backToTop := (T "backToTop") | default "Scroll to top" -}}

<nav class="hextra-toc order-last hidden w-64 shrink-0 xl:block print:hidden px-4" aria-label="table of contents">
  {{- if $toc }}
    <div class="hextra-scrollbar sticky top-16 overflow-y-auto pr-4 pt-6 text-sm [hyphens:auto] max-h-[calc(100vh-var(--navbar-height)-env(safe-area-inset-bottom))] ltr:-mr-4 rtl:-ml-4">
      {{- with .Fragments.Headings -}}
        <p class="mb-4 font-semibold tracking-tight">{{ $onThisPage }}</p>
        {{- range . -}}
          <ul>
            {{- with .Headings -}}{{ template "toc-subheading" (dict "headings" . "level" 0) }}{{- end -}}
          </ul>
        {{- end -}}
      {{- end -}}

      {{- $borderClass := "mt-8 border-t bg-white pt-8 shadow-[0_-12px_16px_white] dark:bg-dark dark:shadow-[0_-12px_16px_#111]" -}}
      {{- if not .Fragments.Headings -}}
        {{- $borderClass = "" -}}
      {{- end -}}

      {{/* TOC bottom part */}}
      <div class="{{ $borderClass }} sticky bottom-0 flex flex-col items-start gap-2 pb-8 dark:border-neutral-800 contrast-more:border-t contrast-more:border-neutral-400 contrast-more:shadow-none contrast-more:dark:border-neutral-400">
        {{- if site.Params.editURL.enable -}}
          {{- $editURL := site.Params.editURL.base | default "" -}}
          {{- with .File -}}{{ $editURL = urls.JoinPath $editURL (replace .Path "\\" "/") }}{{- end -}}
          {{- with .Params.editURL -}}{{ $editURL = . }}{{- end -}}
          <a class="text-xs font-medium text-gray-500 hover:text-gray-900 dark:text-gray-400 dark:hover:text-gray-100 contrast-more:text-gray-800 contrast-more:dark:text-gray-50" href="{{ $editURL }}" target="_blank" rel="noreferer">{{ $editThisPage }}</a>
        {{- end -}}
        {{/* Scroll To Top */}}
        <button aria-hidden="true" id="backToTop" onClick="scrollUp();" class="transition-all transition duration-75 opacity-0 text-xs font-medium text-gray-500 hover:text-gray-900 dark:text-gray-400 dark:hover:text-gray-100 contrast-more:text-gray-800 contrast-more:dark:text-gray-50">
          <span>
            {{- $backToTop -}}
          </span>
          <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor" class="inline ml-1 h-3.5 w-3.5 border rounded-full border-gray-500 hover:border-gray-900 dark:border-gray-400 dark:hover:border-gray-100 contrast-more:border-gray-800 contrast-more:dark:border-gray-50">
            <path stroke-linecap="round" stroke-linejoin="round" d="M4.5 15.75l7.5-7.5 7.5 7.5" />
          </svg>
        </button>
      </div>
    </div>
  {{ end -}}
</nav>

{{/* TOC subheadings component. This is a recursive component that renders a list of headings. */}}
{{- define "toc-subheading" -}}
  {{- $headings := .headings -}}
  {{- $level := .level -}}
  {{- if ge $level 6 -}}
    {{ return }}
  {{- end -}}

  {{- $padding := (mul $level 4) -}}
  {{- $class := cond (eq $level 0) "font-semibold" (printf "ltr:pl-%d rtl:pr-%d" $padding $padding) -}}

  {{- range $headings }}
    {{- if .Title }}
      <li class="my-2 scroll-my-6 scroll-py-6">
        <a class="{{ $class }} inline-block text-gray-500 hover:text-gray-900 dark:text-gray-400 dark:hover:text-gray-300 contrast-more:text-gray-900 contrast-more:underline contrast-more:dark:text-gray-50 w-full break-words" href="#{{ anchorize .ID }}">
          {{- .Title | safeHTML | plainify | htmlUnescape }}
        </a>
      </li>
    {{- end -}}
    {{- with .Headings -}}
      {{ template "toc-subheading" (dict "headings" . "level" (add $level 1)) }}
    {{- end -}}

  {{- end -}}
{{- end -}}
